1. Field of the Invention
The present invention relates generally to a method and system for slurrying fibrous organic materials and removing grit therefrom, and more particularly, but not by way of limitation, to a method and system for slurrying fibrous organic materials such as feedlot fecal waste materials with water and removing grit therefrom.
2. Description of the Prior Art
Various processes and apparatus for converting fermentable fibrous organic materials such as feedlot fecal wastes, e.g., cattle manure, into more valuable and useful products have been developed. For example, a process for converting fermentable fibrous organic materials to useful products is disclosed in our co-pending application Ser. No. 39,026 filed May 14, 1979. Other processes wherein fermentable fibrous organic materials are converted to useful products such as methane gas and protein-rich animal feed supplement are disclosed in U.S. Pat. Nos. 3,838,199 and 3,973,043.
In all of such processes, the fibrous organic materials are combined with a carrier liquid, e.g., water, to form a slurry thereof and the slurry subjected to a fermentation process or processes to produce a protein-rich and hydrocarbon vapor products. The formation of a slurry of fibrous organic materials such as feedlot fecal waste materials is difficult, particularly where the slurry formation must be carried out on a continuous basis. The waste materials usually contain grit, i.e., relatively heavy impurities, such as sand, soil, rocks and other insoluble materials and the organic portions of the waste materials are generally extremely dry and hard. If the waste materials are inadequately suspended in the carrier liquid problems in treating the resulting slurry are encountered such as the plugging off of conduits, inadequate and/or inefficient fermentation, etc. If the grit contained in the waste materials is not removed or inadequately removed, the same problems result as well as requiring clean-out and rework of process apparatus on a continuous basis.
By the present invention an improved method and system for slurrying fibrous organic materials containing grit and removing the grit therefrom is provided which obviates the problems mentioned above.